This invention relates generally to gas turbine engines, and more specifically to methods and apparatus for assembling gas turbine engine fan assemblies.
At least some known gas turbine engines include a fan for supplying air to a compressor that compresses incoming air which is mixed with a fuel and channeled to a combustor wherein the mixture is ignited within a combustion chamber for generating hot combustion gases. The hot combustion gases are channeled downstream to a turbine, which extracts energy from the combustion gases for powering the fan and compressor, as well as producing useful work to propel an aircraft in flight or to power a load, such as an electrical generator.
Known compressors include a rotor assembly that includes at least one row of circumferentially spaced rotor blades. Each rotor blade includes an airfoil that includes a pressure side and a suction side connected together at leading and trailing edges. Each airfoil extends radially outward from a rotor blade platform. Each rotor blade also includes a dovetail that extends radially inward from the platform, and is used to mount the rotor blade within the rotor assembly to a rotor disk or spool. More specifically, at least some known rotor disks include a plurality of circumferentially-spaced dovetail slots that are each sized to receive a respective one of the plurality of rotor blades therein. Known rotor blade dovetails are generally shaped complementary to the dovetail slot to enable the rotor blade dovetails and the rotor disk slot to mate together and form a dovetail assembly. Adapters may be used to facilitate the mating of the dovetails and the slots.
During an installation process, interlocking mid-span dampers extending between adjacent blades, may overlap rather than interlock, if the blades are not inserted substantially simultaneously into the dovetail slots. Know methods of inserting the blade into the dovetails include incremental insertion of each blade in turn until all blades are seated into the dovetail. If, during the installation process, mid-span dampers overlap, the installation process is stopped and the dampers are disengaged before the installation is resumed. If the mid-span dampers become overlapped such that they cannot be disengaged manually, each mid-span damper may need to be non-destructively tested. Because each rotor includes numerous blades and each blade may be handled numerous times during installation, the installation process may be time-consuming and laborious. Additionally, manufacturer requirements may require engines to be removed from an aircraft, or be at least partially disassembled to accommodate the installation process.